photos of oil paintings
Friedrich Leisch
How do I best take photos of oil paintings, such that I don't have too
many reflections?
Obviously, when I direct the flash at the painting, I will see a
bright reflection of the flash. Is it sufficient to point the flash to
the ceiling and use the indirect light? Should I take the painting
outside on a sunny day to actually see what's going on (i.e., which
reflections I get)?
Thanks for any help
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Friedrich Leisch
Institut für Statistik Tel: (+43 1) 58801 4546
Technische Universität Wien Fax: (+43 1) 504 14 98
Wiedner Hauptstraße 8-10/1071 Friedric...@ci.tuwien.ac.at
A-1040 Wien, Austria http://www.ci.tuwien.ac.at/~leisch
PGP public key http://www.ci.tuwien.ac.at/~leisch/pgp.key
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Mr 645
You should try using two strobes placed about 45 degrees to either side.
Modeling light are important to you can see if there is any reflections on the
painting.
Jon
evp...@insync.net
In article <547m2db...@galadriel.ci.tuwien.ac.at>,
Okay, one more time. This is the ideal real world methodology for
photographing oil paintings using electronic flash and daylight balanced
film. Lighting requirements: at least two flash heads, Place one on
either side of the painting, at 45 degrees off axis. if the painting is
sufficiently large then use at two flash heads on each side. the idea here is
to get an even amount of exposure in all four corners and in the center of
the painting. Next: place a large (12"x12") polarizing filter in front of
each of your light sources. The polarization angle for these filters must all
be the same. polarization angle is usually marked on the filter frames by a
double set of arrows pointing away from each other. You want all light
polarized in the same direction. Camera: ideally you want a longer than
normal focal length lens. It does not have to be a special flat field or
macro lens, but that doesn't hurt (or help, unless the photographs you are
making are 1:1.) square up the camera to the artwork so that the camera's
film plane is parallel to the plane of the painting and the center of the
painting is in the center of your view finder. I have found the easiest way
to do this is to put a mirror over the center of the painting parallel to the
surface of the painting and I look through the camera till I see a perfect
reflection of the center of the lens in the center of the viewfinder. Lock
your camera's position down. check once again for alignment. Getting rid
of those pesky hot spots. Look through the polarising filter for the camera
and rotate it until you see all hot spots go away. What you are doing is a
technique called cross polarization. If the axis of polarization for your
lights is up/down you want the polarization axis for your lens to be
left/right. or vice versa, it doesn't matter so long as these axises are
oriented 90 degrees from each other. If you have done this right all
reflections will have vanished from the surface of the painting.
Determining exposure: I like to take a reading at all four corners and the
center of the painting. set your hand-held incident at your film's iso
reading (I rate most Kodak & Fuji ISO 100 films at ISO 80) and gdo what you
need to do in terms of adjusting light placement or angle so that all five
readings are within 1/10th of a stop of each other. This is with the
polarizers on the lights. Most camera polarizers need a 1.5 to 2 stop
exposure increase to compensate, so either you can open up your lens that
much after you take your meter reading, or you can reduce your effective film
ISO that much. (For example if you usually rate your film at 100, if you have
determined that your polazizers need two stops of compensation, now change
your meter's iso to 25.) Now it is time to make some pictures! make sure to
bracket (I like 1/3rd stop increments) When you get back your film you will
think wow these are great, that Ellis guy sure knew what he was writing
about! Or you'll be saying, hey, how come there is no detail in the shadows
but these highlights look fine ( or vice versa) Since i don't know what the
paintings you are copying look like or how old they are or what state they
are in, or what materials make up the individual pigments, or which glazes,
varnishes etc. the artist is using, the only answer i have is have a
professional do the copy work. Expensive? probably but it is their headache
to get it right. Cheers, Ellis
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